1. Field of the Invention
The present invention relates to package structures, and, more particularly, to a package structure that is protected from electromagnetic interferences and a method for fabricating the same.
2. Description of Related Art
With the rapid growth in electronic industry, most electronic products have been developed towards the goal for miniaturization and high speed, particularly as the modern communication techniques have been widely incorporated in various electronic products. However, as the electronic products include high frequency chips, and these chips are easily affected by electromagnetic interferences (EMI) due to the adjacent integrated circuits and digital signal processors (DSP), an electromagnetic shielding treatment is often required.
A conventional radio frequency (RF) module 1 that is protected from EMI is illustrated in FIGS. 1A to 1C. A plurality of RF chips 11a and 11b and non-RF electronic components 11 are electrically connected and incorporated on a packaging substrate 10. The RF chips 11a and 11b and the non-RF electronic components 11 are encapsulated by an encapsulating layer 13 such as epoxy resin. A thin metal film 14 is formed on the encapsulating layer 13. The RF chips 11a and 11b, the non-RF electronic components 11 and the packaging substrate 10 in the RF module 1 can be prevented from damages caused by outside moist or contaminants by the encapsulating layer 13, and the RF chip 11a and 11b are protected from EMI via the thin metal film 14.
Although the periphery of the RF module 1 is encapsulated by the thin metal film 14 and protected from EMI, if the RF chips 11a and 11b are low frequency components, it is difficult for the single thin metal film 14 to protect the RF module 1 from EMI efficiently.
Therefore, there is an urgent need for overcoming the drawbacks of the prior art.